= Solution
Launch and arrival occur on the capsule's own worldline, so its clock measures the <proper time>. In the ship frame its <Lorentz factor> is $\gamma_{c/s}=(1-0.9^2)^{-1/2}$; therefore
$$
\boxed{\Delta\tau_c=\frac{\Delta t_s}{\gamma_{c/s}}=\Delta t_s\sqrt{1-0.9^2}\simeq0.131211\,\mathrm{day}\simeq3.1491\,\mathrm h.}
$$
This uses the station-frame distance convention stated in <10/c/i>. With a one-light-day distance in the ship frame instead, it becomes $\Delta\tau_c=\sqrt{0.19}/1.75\,\mathrm{day}\simeq0.249080\,\mathrm{day}$. The uncertainty is a distance-frame convention in the wording, not a missing figure or an unanswered mathematical part.
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